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A Study to Develop a Curriculum in Industrial Destructive Testing Procedures for Ferrous and Non-Ferrous Metals at the University LevelGeary, Michael Robert 05 1900 (has links)
The problem of this study was to develop a curriculum based on present destructive testing procedures used in industry dealing with the mechanical properties of ferrous and non-ferrous metals, and to organize the curriculum at the university level.
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Forecasting The Prices Of Non-ferrous Metals With Garch Models & / Volatility Spillover From World Oil Market To Non-ferrous Metal MarketsBulut, Burcak 01 August 2010 (has links) (PDF)
In the first part of this thesis the prices of six non-ferrous metals (aluminum, copper, lead, nickel, tin, and zinc) are used to assess the forecasting performance of GARCH models. We find that the forecasting performances of GARCH, EGARCH, and TGARCH models are similar. However, we suggest the use of the GARCH model because it is more parsimonious and has a slightly better statistical performance than the other two.
In the second part, the prices of six non-ferrous metals and the price of crude oil are used to examine the dynamic links between oil and metal returns by using the BEKK specification of the multivariate GARCH model and the Granger causality-in-variance tests. Results of our study agree with the previous studies in that the crude oil market volatility leads all non-ferrous metal markets.
In order to move as far away from the effects of 9/11, daily data for the period December 12, 2003 &ndash / December 15, 2008 is used for the data analysis part of the thesis.
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A case study of non-ferrous metal theft at a selected mine in South AfricaCoetzee, Ben 06 1900 (has links)
The threat posed by non-ferrous metal theft to industries in South Africa is substantial
but is also regarded with indifference. A reason for this view may be that the criminal act
is ordinarily not accompanied by violence and the target of the crime is an object that is
far removed from the vicinity of the majority of South Africans. Non-ferrous metal theft
may sometimes even be erroneously termed a victimless crime. This study endeavours to
shed light on the complexities of non-ferrous metal theft and the industrial dangers that
may be suffered if this crime is not eradicated. A case study from the mining industry
was used to examine the nature and extent of non-ferrous metal theft. A mixed methods
approach was followed in terms of which qualitative and quantitative research was done
sequentially to provide the best possible representation of the situation. The participant
allowed access to data over a six-year period as well as access to mine employees for
interviews to assist with understanding the safety and security measures that the mine
put in place to protect its workforce. This information led to another realisation, namely
that if non-ferrous metal thieves cut an electricity supply line that is critical for life
support and transportation in the mine, mineworkers may succumb to the harsh
conditions underground. It also became evident that the police and the criminal justice
system must develop a better understanding of the seriousness of non-ferrous metal
theft. If this does not happen in the near future, managing the consequences of nonferrous
metal theft at South African mines will become a mammoth task. Such mines and
other industries affected by non-ferrous metal related theft must collaborate with each
other and the police in order to understand the nature of the crime and to ensure that
the prosecution of the perpetrators is handled properly. These industries should also
subscribe to a pragmatic approach to crime prevention whereby various components
from different crime prevention strategies are used to address the issues being
experienced and whereby a unique crime prevention model for each industry and mining
site can be developed. / Police Practice / M.A. (Policing)
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A case study of non-ferrous metal theft at a selected mine in South AfricaCoetzee, Ben 06 1900 (has links)
The threat posed by non-ferrous metal theft to industries in South Africa is substantial
but is also regarded with indifference. A reason for this view may be that the criminal act
is ordinarily not accompanied by violence and the target of the crime is an object that is
far removed from the vicinity of the majority of South Africans. Non-ferrous metal theft
may sometimes even be erroneously termed a victimless crime. This study endeavours to
shed light on the complexities of non-ferrous metal theft and the industrial dangers that
may be suffered if this crime is not eradicated. A case study from the mining industry
was used to examine the nature and extent of non-ferrous metal theft. A mixed methods
approach was followed in terms of which qualitative and quantitative research was done
sequentially to provide the best possible representation of the situation. The participant
allowed access to data over a six-year period as well as access to mine employees for
interviews to assist with understanding the safety and security measures that the mine
put in place to protect its workforce. This information led to another realisation, namely
that if non-ferrous metal thieves cut an electricity supply line that is critical for life
support and transportation in the mine, mineworkers may succumb to the harsh
conditions underground. It also became evident that the police and the criminal justice
system must develop a better understanding of the seriousness of non-ferrous metal
theft. If this does not happen in the near future, managing the consequences of nonferrous
metal theft at South African mines will become a mammoth task. Such mines and
other industries affected by non-ferrous metal related theft must collaborate with each
other and the police in order to understand the nature of the crime and to ensure that
the prosecution of the perpetrators is handled properly. These industries should also
subscribe to a pragmatic approach to crime prevention whereby various components
from different crime prevention strategies are used to address the issues being
experienced and whereby a unique crime prevention model for each industry and mining
site can be developed. / Police Practice / M.A. (Policing)
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Microstructure Design And Interfacial Effects On Thermoelectric Properties Of Bi-Sb-Te SystemFemi, Olu Emmanuel 06 1900 (has links) (PDF)
Climate change is a subject of deep distress in today’s world. Over dependence on hydrocarbon has resulted in serious environmental problems. Rising sea level, global warming and ozone layer depletion are the mainstream of any discuss world over. The collective goal of cutting carbon emission by the year 2020has prompted the search for clean, alternative energy sources. This effort are already yielding good reward as other forms of energy such as solar, wind, nuclear and hydro have received huge investment and renew interest over the past decade.
Thermoelectric materials over the past decades have been tipped to replace conventional means of power generations as these materials have the ability to convert heat to electrical energy and vice versa. They are simple, have no moving parts and use no greenhouse gases. But the major drawback of these materials is their low conversion efficiency. Hence there is a need to enhance the efficiency of thermoelectric material to fulfill their undeniable potentials.
A parameter called the thermoelectric figure of merit, ZT defines the efficiency of a thermoelectric material. ZT relates three non-mutually exclusive transport properties namely Seebeck coefficient, electrical conductivity and thermal conductivity. Efficient thermoelectric material should possess high Seebeck coefficient, high electrical conductivity and low thermal conductivity. Hence, one of the interesting ideas in the area of thermoelectric research is the concept of designing a bulk material with high density of phonon scattering centers so has to reduce the lattice contribution to thermal conductivity but at the same time have minimum impact oncharge carriers. This is usually achieved by utilizing interphase and grain boundaries which are localized defects to scatter phonons. The volume fraction of the grain/interphase boundaries can be control through phase modification and microstructure design. This thesis is centered on Bi-Sb-Te systems which are the present room temperature state of the earth thermoelectric material. The investigation revolves around developing a new kind of
microstructure in the well-studied Bi-Sb-Te system that shows tremendous potential as a means to reduce lattice contribution to thermal conductivity. The idea of having both p and n-type thermoelectric material preferably from the same material was also a motivation in our investigation. The thesis isdivided into six chapters.
The first chapter introduces the concept of thermoelectricity i.e. the direct conversion of thermal energy into electricity. The physics involved and contribution of individual to the science of thermoelectricity were enumerated. Efficiency, optimization and material selection for better thermoelectric performance were briefly enumerated. Prospective materials that are currently been investigated for better thermoelectric properties were also mentioned. The structure of the Bi-Sb-Te system which is the focus of this thesis is present in this chapter including doping effect on the thermoelectric performance of the system as well as the various methods present been employed to improve the thermoelectric properties of the system. Finally the chapter enumerates the scope and object of the present thesis.
The different experimental procedures adopted in the present thesis arediscussed in chapter 2. The details of different processing routes followed to synthesize flame-melted ingots, flame-melted + low temperature milled (cryo milling) + spark plasma sintering (SPS) alloy and flame-melted + melt spinning + spark plasma sintering (SPS) alloy, are discussed followed by the various structural and functional characterization techniques. The unique advantage of the spark plasma sintering techniques over the conventional sintering method was talked out in detail. The structural characterizations performed on the synthesized alloys include XRD, SEM and whilethe functional characterizations comprised of Hall measurement, Seebeck coefficient, electrical resistivity and thermal conductivity measurements.
Thermoelectric properties of selected composition of Bi-Sb-Te synthesized via flame-melting are presented in chapter 3.Detail study of four analyzed compositions namelyBi24Sb20Te56, Bi20Sb12Te69, Bi16Sb5Te79 and Bi29Sb11Te60resulted in four unique microstructure and different volume fraction of primary and secondary phases. The resultant morphologies of the microstructure were observed to have influence the thermoelectric behavior corresponding to each composition. The sole influence of anti-structural defects on the conductivity type and the role of microstructure morphologies and length scale were understood in this chapter. Samples with segregated Te and a solid solution BiSbTe3(eutectic morphology) form an n-type thermoelectric material while samples with only solid solution BiSbTe3 forms a p-type thermoelectric material. Pair of n-type and p-type material was obtained without the introduction of external dopant.The pair shows good compatibility factorsuitable for thermoelectric device.
In chapter 4, the thermoelectric properties of four selected composition of Bi-Sb-Te synthesized via low temperature milling plus spark plasma sintering is addressed. The analyzed compositions are as follows Bi24Sb20Te56, Bi18Sb11Te71, Bi17Sb6Te77, and Bi28Sb15Te57 respectively. The effect of low temperature milling combine with the prospect of minimum grain growth of spark plasma sintering on the thermoelectric properties of the selected compositions were determined. Samples with eutectic morphology which would otherwise scatter charge carriers were observed to have the highest carrier mobility as a result of high volume fraction of Te phase which serves as a donor injecting excess electrons into the system. The impact of small grain size was observed on the transport properties of the sample Bi28Sb15Te57 with the highest electrical resistivity, the best Seebeck coefficient and the lowest thermal conductivity. Pair of n-type and p-type material was obtained without the introduction of external doping elements. The pairshows good compatibility factor suitable for segmented thermoelectric device.
Chapter 5 narrates the thermoelectric properties of four compositions namely Bi30Sb13Te58, Bi23Sb13Te65, Bi18Sb5Te77 and Bi23Sb20Te58subjected to melt spinning plus spark plasma sintering.High cooling rate obtained during melt spinning process was observed in this chapter to cause a shift of composition which resulted in a microstructure morphology with eutectic colonies that is predominantly Te rich. These Te rich colonies in the sample Bi30Sb13Te58 was observed to change the conductivity type of the sample from an otherwise p-type to n-type while also aiding bipolar conduction which was detrimental to the overall thermoelectric performance of the alloy. Segregated Te in the form of eutectic morphology helps to inject excess electron into the bulk of the sample Bi23Sb13Te65 and Bi18Sb5Te77hereby increases the observed electrical conductivity which by virtue of the microstructure morphology is expected to be low. As a result of the processing routes, all four compositions in this chapter shown-type conductivity.
Chapter 6 presents the summary of the important conclusions drawn from this work.
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A criminological analysis of copper cable theft in GautengPretorius, William Lyon 02 October 2013 (has links)
This dissertation focuses on the phenomenon of copper cable theft within the Gauteng Province of South Africa. Data was collected from literature sources as well as from security professionals combating copper theft.
There are five primary objectives in this research:
1. To explore and to describe the extent and the impact of copper cable theft.
2. To gain insight into the profile and the modus operandi of the offender.
3. To evaluate current intervention measures used to combat the copper cable theft.
4. To describe the general factors limiting the success of combating copper cable theft.
5. To recommend probable intervention measures with which to combat copper cable theft.
Semi-structured interviews were conducted with responsible security officials of victim stakeholder groups in Gauteng. It was established that copper cable theft is currently a very serious crime that deserves both attention and quick intervention before it does irreparable damage to the utility infrastructure of Gauteng, in particular, and in fact to all these infrastructures in South Africa. / Criminology / M.A. (Criminology)
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A criminological analysis of copper cable theft in GautengPretorius, William Lyon 12 1900 (has links)
This dissertation focuses on the phenomenon of copper cable theft within the Gauteng Province of South Africa. Data was collected from literature sources as well as from security professionals combating copper theft.
There are five primary objectives in this research:
1. To explore and to describe the extent and the impact of copper cable theft.
2. To gain insight into the profile and the modus operandi of the offender.
3. To evaluate current intervention measures used to combat the copper cable theft.
4. To describe the general factors limiting the success of combating copper cable theft.
5. To recommend probable intervention measures with which to combat copper cable theft.
Semi-structured interviews were conducted with responsible security officials of victim stakeholder groups in Gauteng. It was established that copper cable theft is currently a very serious crime that deserves both attention and quick intervention before it does irreparable damage to the utility infrastructure of Gauteng, in particular, and in fact to all these infrastructures in South Africa. / Criminology and Security Science / M.A. (Criminology)
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Examining the significance of modus operandi information in copper theft investigationLiebenberg, Andre Sarel 02 1900 (has links)
This study sought to examine the significance of modus operandi information in the investigation of copper theft. Data was collected by means of a literature study and individual semi-structured interviews conducted with detectives at the SAPS Philippi East, in the Nyanga policing cluster, in the Western Cape, to promote knowledge and understanding of the significance of modus operandi information in copper theft investigations. A comprehensive literature study, concerning the dynamics of modus operandi information in forensic investigation and copper theft in South Africa, was conducted. From the results of this research, it appears that participants do realize the significance of modus operandi information in the investigation of copper theft. It is, however, evident that they do not optimally utilize modus operandi information regarding copper thieves as a result of limited experience, case docket overload, and the inaccessibility of available data – all of which inhibit the establishment of modus operandi information pertaining to copper thieves. Role-players in the copper theft investigation sphere isolate themselves from each other and do not share the available modus operandi information amongst each other; these results in a non-systematic integrated approach to copper theft investigation. The study identifies the challenges and shortcomings, experienced by detectives at SAPS Philippi East, which inhibit the optimal utilization of modus operandi information in the investigation of copper theft. The study then puts forward a set of recommendations that could assist the SAPS, the relevant parastatals and other role-players in enhancing the utilization of such information. / Criminology and Security Science / M. Tech. (Forensic Investigation)
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An evaluation of the impact of the Non-ferrous Metals Crime Combating Committee on copper cable theftLiebenberg, Andre Sarel 11 1900 (has links)
English, Zulu and Northern Sotho summaries / This study aims to evaluate the Non-Ferrous Metals Crime Combating Committee's impact on combating copper cable theft in South Africa. Data was collected via in-depth interviews with awaiting trial detainees charged with copper cable theft at the Pollsmoor Correctional Centre in the Western Cape; members of the Mpumalanga and Gauteng Provincial Non-Ferrous Metals Crime Combating Committee; members of Business Against Crime South Africa; and investigators attached to Combined Private Investigations who investigate copper theft nationally. The in-depth interviews provided a comprehensive understanding of participant experiences relating to the impact of the Non-Ferrous Metals Crime Combating Committee on the combating of copper cable theft in South Africa. Moreover, the researcher performed a thorough literature study of the phenomenon locally and internationally.
Research findings indicate shortcomings in the Non-Ferrous Metals Crime Combating Committee's effectiveness, limiting its impact on preventing copper cable theft. Based on these findings, the study recommends that the Non-Ferrous Metals Crime Combating Committee be replaced with a specialised South African Police Service Non-Ferrous Metals Theft Unit. Consequently, this study puts forward a set of recommendations proposing a systematic pro-active plan to address and minimise copper cable theft in South Africa. The proposed plan convincingly presents practical solutions to minimise copper cable theft and contributes to the current body of scholarship on copper cable theft in South Africa. / Inhloso yalolu cwaningo ukuhlola umthelela wohlelo lwe-Non-Ferrous Metals Crime Combating Committee mayelana nokuqedwa kokutshontshwa kwentambo yogesi (copper cable). Idatha iqoqwe ngokusebenzisa izinhlolovo ezijulile ezenziwa ngokusebenzisa iziboshwa eziboshelwe izintambo zikagesi ezisamele ukugwetshwa ejele lase Pollsmoor Correctional Centre ngaseNtshonalanga Kapa, amalunga eMpumalanga and Gauteng Provincial Non-Ferrous Metals Crime Combating Committee, amalunga eBusiness Against Crime South Africa kanye nabaphenyi abahambisana nophiko lweCombined Private Investigations oluphenya ukutshontshwa kwezintambo zikagesi ezweni lonke. Lezi zinhlolovo ezijulile zinikeze ulwazi olubanzi lwabadlalindima olumayelana nomthelela weNon-Ferrous Metals Crime Combating Committee mayelana nokuqedwa kokutshontshwa kwezintambo zikagesi. Ngaphezu kwalokho, umcwaningi wenze ucwaningo olunzulu lombhalo wobuciko mayelana nokutshontshwa kwezintambo zikagesi lapha ekhaya kanye nasemhlabeni wonke jikelele.
Ulwazi olutholakele lukhombisa iziqi ezikhinyabeza ukusebenza kahle kweKomithi mayelana nokuvimbela umthelela walo mayelana nokutshontshwa kwezintambo zikagesi. Ngezizathu ezisuselwa phezu kwalolu lwazi, lolu cwaningo lubeka phambili isethi lezincomo ezinganceda iKomiti ekuqiniseni umthintela walo ngokuhlongoza uhlelo olugqugquzelayo lokunciphisa izinga lokutshontshwa kwezintambo zikagesi eNingizimu Afrika. Lolu hlelo oluhlongoziwe ngaphandle kokungabaza lwethula izixazululo ezenzeka empilweni yangempela ukunciphisa ukwetshiwa kwezintambo zikagesi kanti lokhu kunegalelo kwiziko lamanje futhi luqhubekisa iziko lamanje lwezifundo esimayelana nokwetshiwa kwezintambo zikagesi. / Maikemisetso a thutelo ye ke go lekola khuetso ya Komiti ya Twantsho ya Bosenyi bja Dimetale tse di Sego tsa Tshipi ka ga go lwantsha kutso ya megala ya koporo. Datha e kgobokeditswe ka mokgwa wa ditherisano tse di tseneletsego tseo di sepeditswego le mahodu a megala ya koporo ao a golegilwego ao a letetsego go sekiswa Senthareng ya Tshokollo ya Pollsmoor go la Kapa Bodikela, maloko a Diprofense tsa Mpumalanga le Gauteng a Komiti ya Twantsho ya Bosenyi bja Dimetale tse di sego tsa Tshipi, maloko a Dikgwebo tsa Kgahlanong le Bosenyi tsa Afrika Borwa le banyakisisi bao ba dirisanago le Dinyakisiso tsa Praebete tse Kopantswego tseo di nyakisisago kutso ya koporo kemong ya bosetshaba. Ditherisano tse di tseneletsego tse di file kwesiso ka botlalo ya maitemogelo a batseakarolo ye e sepelelanago le khuetso ya Komiti ya Twantsho ya Bosenyi bja Dimetale tse di sego tsa Tshipi ka ga go lwantsha kutso ya megala ya koporo. Gape, monyakisisi o dirile thutelo ya dingwalo ka botebo ya kutso ya megala ya koporo tikologong ya leagong le kemong ya boditshabatshaba.
Dikhwetso tsa dinyakisiso di supa mafokodi ao a lebanego bokgoni bja Komiti tshitisong ya khuetso ya yona go kutso ya megala ya koporo. Go ya ka dikhwetso tse, thutelo ye e hlagisa sehlopha sa dikeletso tseo di ka thusago Komiti go tswetsa khuetso ya yona pele ka go sisinya leano la go itokisetsa seemo se ka diregago ka mokgwa wo o beakantswego go fokotsa kutso ya megala ya koporo ka Afrika Borwa. Leano leo le sisintswego le hlagisa ka mo go kgodisago ditharollo tse di ka phethagatswago go fokotsa kutso ya megala ya koporo ka gona la ba la seabe go le go tswetsa pele popego ya bjale ya borutegi ka ga kutso ya megala ya koporo. / Criminology and Security Science / Ph. D. (Criminal Justice)
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